1. Field of the Invention
The present invention relates to an information processing apparatus and a system therefor, for processing information containing at least image information.
2. Related Background Art
FIG. 10 shows an example of display in a conventional information processing apparatus.
There are illustrated image display frames 111 to 114 of the information processing apparatus; a control panel 101 including various buttons for operating the information processing apparatus; an image fast forward button 102; an image reproduction start button 103; an image reproduction reverse button 104; and an image reproduction stop button 105.
FIG. 8 is a block diagram of an information processing apparatus, constituting a terminal in the conventional system.
There are illustrated a ROM (Read Only Memory) 801 for storing programs for loading the operating system or the like into the information processing apparatus; a RAM (Random Access Memory) 802 serving as a work area in the execution of the operating system, programs or various data from an external memory device 808; a memory bus 803 for data exchange between the CPU (Central Processing Unit) and the ROM or RAM; a CPU 804; a CRT (Cathode Ray Tube) 809 serving as a display for displaying characters and images; an I/O bus 805 for data exchange between I/O devices such as keyboard, mouse and hard disk and the CPU; a keyboard 806 constituting an input device; a mouse 907 constituting a coordinate input device; an external memory device 808 such as a hard disk, for storage of the operating system, programs and data and for use as a swap device; and a VRAM 810 on which a bit map image of characters and images to be displayed on the CRT 809 is developed.
An image input unit 811 is connected to a video camera 902 to be explained later and an image analog signal entered from a CCD (Charge-Coupled Device) in the video camera 902 is converted into a digital signal and developed on a RAM in the image input unit 811.
The CPU 804 can read thus developed data through the I/O bus.
A voice input unit 812 is connected, like the image input unit 811, to the video camera 902, whereby an analog voice signal, entered from a microphone connected to the video camera 902, is converted into a digital signal and developed in the RAM in the voice input unit 812.
The CPU 804 can also read the above-mentioned data through the I/O bus.
A voice output unit (loudspeaker) 903 converts the digital voice data, stored in the RAM of the unit, into an analog signal for external release in the form of acoustic signal.
There are also provided an image compression/extension unit 813 for compressing and extending image and voice data; a network transmission/reception unit 814 for controlling a network; and a network channel 815.
FIG. 9 shows an example of the configuration of a conventional image processing system. An information processing apparatus 5 is basically same, in configuration, as apparatus 1 to 4, except for omission of units 902 and 903.
A main body 901 of the information processing apparatus incorporates the ROM 801, the RAM 802, the memory bus 803, the CPU 804, the VRAM 810, the I/O bus 805, the external memory device 808 and the network transmission/reception unit 814. There are also provided, as explained in the foregoing, the CRT 809 constituting the display for displaying the characters and images of the information processing apparatus; the keyboard 806 for entering characters or instructing operations; the mouse 807 constituting the coordinate input means; the video camera 902 for entering image and voice; the microphone/loudspeaker 903 for voice input/output; and the bus-structured network 815 such as Ethernet.
Windows 111 to 114 in FIG. 10 shows an example of display of the information processing apparatus 5 and display the images from the video cameras 902 connected to the information processing apparatus 1 to 4.
The voice entered from the microphones attached to the video camera 902 are released from the loudspeakers 903 associated with the information processing apparatus.
The information processing apparatus 1 to 4 broadcast the images from the video cameras to the network 815, but the efficiency of transmission will be deteriorated because of mutual collisions in case of simultaneous transmissions by the information processing apparatus 1 to 4, as the data amount becomes excessively large in comparison with the line capacity of the network 815.
For this reason, transmission control is conducted by the information processing apparatus 5, in the manner to be explained in the following with reference to FIG. 11.
It is registered in advance, in the information processing apparatus 5, that the system is constituted by the information processing apparatus 1 to 4.
When the transmission control is initiated according to a program of the ROM 801 and under the control of the CPU 804 in the information processing apparatus 5 (step 1101), the apparatus 5 sets a variable Count, for setting the information processing apparatus for which the data transmission is permitted, to xe2x80x9c1xe2x80x9d (step 1102). Then the information processing apparatus 5 transmits a transmission permission packet, for permitting the transmission of image and sound data of a frame, to an information processing apparatus corresponding to the value of the Count (step 1103). Then there is awaited the completion of transmission by the information processing apparatus corresponding to the value of the Count, to which the permission for transmission has been given (step 1104). The completion of transmission is identified by the reception of a transmission end packet, transmitted from the information processing apparatus corresponding to the value of the Count, to which the permission for transmission has been given. Then the Count is increased by a step to give the permission for transmission to a next information processing apparatus (step 1105). Then the value of the Count is compared with 4, and, if it is larger than 4, (step 1106), it is set at xe2x80x9c1xe2x80x9d as such value exceeds the maximum number of the information processing apparatus constituting the system of the present example (step 1101). If the value of the Count does not exceed 4 (step 1106), a transmission permission packet is transmitted (step 1103) to an information processing apparatus corresponding to the value of the Count.
Now there will be explained the transmission of the image and voice data, with reference to FIGS. 3 and 8. The image data obtained from the camera are read from the RAM in the image input unit 811, and the voice data are read from the RAM in the voice input unit (step 302). The image data are compressed in the image compression unit 813 (step 303), then the compressed image data and the voice data are connected and are formed into packets (step 304). Then, in response to the permission for transmission from the information processing apparatus 5 (step 305), all the generated packets are transmitted in succession to the network 815 (step 307). Subsequently a transmission end packet, indicating the completion of transmission, is transmitted to the information processing apparatus 5 which effects the transmission control (step 308), and the sequence returns to the step 302.
In the following explained is the reception of the image and voice data, with reference to FIGS. 4 and 8.
At first there is awaited the reception of the image and voice packet (step 402). When an image packet is received, the source of transmission of the packet is discriminated (step 404), and data are taken out from the packet (step 405). Then there is discriminated whether the image and voice data of an image frame have been collected (step 406), and, if not, there is awaited the reception of another image and voice packet (step 402). When the image and voice data of an image frame have been collected, there is conducted generation of the image and voice data. As the image data are compressed, they are extended in the image compression/extension unit 813 (step 407). Then the image data are stored in the RAM in the image input unit 811, and displayed in an area assigned for the information processing apparatus of the source of transmission. Also the voice data are stored in the RAM in the voice input unit 812, and the voice is released (step 408). Subsequently there is awaited the reception of a next image and voice packet (step 402).
In the following there will be explained, with reference to FIG. 12, a program for analyzing the content of the received packet and transferring the control to a suitable program according to thus analyzed content. At first there is awaited the reception of a packet (step 1202). When a packet is received, the header thereof is analyzed, and, if it is an image packet (step 1203), the sequence proceeds from a step 1204 to a step 403 in FIG. 4. If the received packet is not an image packet, there is discriminated whether it is a transmission permission packet (step 1205), and, if so, the sequence proceeds from a step 1206 to a step 306. If not, there is executed another packet process (step 1207), and the packet reception is again awaited (step 1202).
In the above-explained configuration, the information processing apparatus 5 effecting the transmission control effects stepwise upcount of the variable Count, and transmits a permission for transmission of a frame to the information processing apparatus of a number corresponding to the value of the Count.
Consequently, the frame rate of the image transmitted by the plural information processing apparatuses constituting the network is always substantially same, and it is not possible to vary the frame rate in the receiving side of the image. Also, it is not possible to vary the frame rate among such plural information processing apparatuses.
On the other hand, for simultaneously displaying plural images on the display of an information processing apparatus, there is generally required a very large computing power because of the very large amount of information involved in the image. For this reason, it is difficult to display plural moving images respectively with the maximum frame rate.
However, among the plural images simultaneously displayed, the user usually pays attention only to one or two images, so that the computing power is wasted for other images. However, a simple lowering of the frame rate of the plural images in order to avoid such waste of the computing power results in deterioration of the quality of the displayed images, and such method is not effective as the displayed images become unpleasant to observe.
On the other hand, there may be a difference in the processing ability between the information processing apparatus of the transmitting side and that of the receiving side. For example, if the computing power of the receiving side is smaller than that of the transmitting side, the image display at the receiving side has to be made with a frame rate lower than that of the transmission. For this reason, in case plural computers with different computing powers are used in the image receiving side, the frame rate of the transmission has to be lowered in consideration of the computer of the lowest computing power, so that the computing powers of other computers cannot be fully exploited and the displayed images are deteriorated in quality.
In consideration of the foregoing, an object of the present invention is to provide an information processing apparatus and an information processing system, not associated with the drawbacks mentioned above.
Another object of the present invention is to provide an information processing apparatus and an information processing system, in which the frame rate of the image to be processed is rendered variable thereby achieving satisfactory image processing.
Still another object of the present invention is to provide an information processing apparatus and an information processing system, capable of satisfactory image processing according to the processing ability of respective information processing apparatus.
Still another object of the present invention is to provide an information processing apparatus capable of satisfactory image generation.
Still another object of the present invention is to provide an information processing apparatus and an information processing system, provided with novel functions.
Still other objects of the present invention, and the features thereof, will become fully apparent from the following detailed description, which is to be taken in conjunction with the attached drawings.